Dishwashing apparatus



March 15, 1938. w- R. ADAMS ET AL DISHWASHING APPARATUS Filed April 5, 1935 INVENTOR` s sc Y m @im IB A R- ,MW mf L0 u WG. Y B

Patented Mar. 15, 1938 QISHWASHING APPARATUS William R. Adams and Gordon B. Grace, San

v Francisco, Calif.

Application April 5, 1935, Serial No. 14,774

5 claims.

This invention relates to dish-washing machines and has for its objects a` more compact and `a more eiicient machine than has heretofore been available and which machine is eco- 5 nomical in operation and simple in construction. Another object is the provision of a rinse tank in combination with the washing tank and improved means for replenishing the washing tank with heated water and for maintaining the water heated in the rinse tank and washing tank. Other objects and advantages will appear in the specification and drawing.

In the drawing, Fig. 1 is a plan View of our` machine.

1 5 Fig. 2 is asectional view as seen from line 2 2 4 4 of Fig. 1.

Fig. 5 is a sectional view taken along the line 5-5 of Fig. 2.

Fig. 6 is a perspective Aview of a portion of an inner wall of the washing tank of Fig. 1 adjacent the rinse tank.

Fig. 'I is an enlarged sectionalview of the casting through which the propeller shaft extends.

Fig. 8 is an enlarged fragmentary elevation of the spring and bell crank'on the rinse tank that operates the water inlet valve.

Brieiiy described, we provide lav rectangular dish-washing tank and adjacent thereto a rectangular rinse tank with a common separating wall between the two tanks. Both tanks have drain openings in their bottoms adapted to connect yto a sewer. Means is provided for limiting the maximum water level in the dish-washing tankl below Flg.'4 is a sectional view taken along the line\ a maximum water level in the rinse tank, and the 40 maximum water level in the rinse tank is regulated by an overiiow opening in the wall between the wash4 and rinse tank whereby the water from the rinse tank ows into the wash tank upon rising to said opening.

'I'he rinse tank is provided with means adapted to automatically open a source of fresh water to admit the same to the rinsetank upon dishes being placed in the rinse tank. Heating means is provided for heating the water of the rinse tank, which. heating means is also arranged and adapted toalso help to heat the water in the dish-washing tank to maintain it at the proper temperature.

Associated with the dish-.washing tank are large water injecting slots iii opposite ends o1' the tank at about the same height from the bottom oi the tank, and large conduits, each extending at one end respectively from one of the slots to adjacent opposite sides of a motor driven screw propeller positioned in the bottom of the dishwashing tank at their oppositeends. The propeller, slots and conduits are relatively proportioned and arranged so as to enable free circulation of the water' without building up a back pressure by reason of 'any restriction of the conduits and dschargeslots to a degree below the capacity of the propellerto deliver'water through the conduits land slots. For example, such proportioned machine is generally shown in the drawing in` which the dish-washing tank is about.y 17 inches 1 square with a working capacity of about v11 gallons of water. With about a five-inch propeller in the bottom andoiset slots in two opposite ends of about 7 x 2*/'2 inches, which slots connect by conduitsfoi cross sectional diameter substantiallythe saineas the dimensionsof the slots, we circulate the eleven gallons of water at arate appreciably in excess of 200 gallons per minute at a propeller speed of approximately 1750 R.. P. M.

The movement of the water in the dish-washing tank is generally in three major directions, namely, horizontally and upwardly across the tank in opposite directions, downwardly towardv l the propeller in the bottom of the tank, and a rotary movement, the latter vbeing less pronounced than the former two movements. l

The eilect o f the principle of operation generally is similar to that of,plaing the dishes in a large conduit -iilled with water and rapidly moving the entire body of water through the conduit. The dishes themselves break up the general directional ilow of the water to some extent and in our arrangement in which there vare several major and distinct changes effected inthe directional ii'ow b'y reason of the'oiiset discharge slots in opposite ends and .the propeller in the bottom of the tank, a complete scouring of the dishes resuits and we have found that the time for a complete cleansing of .a basket of soiled dishes is accomplished in from eight to fteen seconds time, according to whether the food particles on the dishes are moist orare dried thereon, the latter time being the average maximum time required under the most unfavorable conditions encounteredin homes, clubs or public eating places. Y

In detail 4my machine comprises a vrectangular open topmain ltank with a vertical partition 3 dividing the main tank into a rectangular dishwashing tank I and a rectangular rinse tank 2. An inner wall is positioned in spaced opposed relation to wall 3 adjacent thereto, which inner wall is vertically divided about centrally thereof into portions 4, 5. An inner wall 6 is positioned in spaced opposed relation to end wall 'I of the main tank. 'Ihese two inner walls are within the dishwashing tank and accordingly form two opposite inner end walls of said tank, while the other two oppositel walls 8 and 9 comprise portions of the rear and front main walls of the tank.

Referring to the portions 4 and 5 which make up one inner end wall of the dish-washing tank adjacent wall 3, the portion 5 is perforated in its face as at I6. The portion 4 is secured along one side edge to front wall 9 of the tank and along its opposite edge it is bent at right angles to form a flange I I that is secured along its free edge to wall 3.

The inner wall 6 extendsbetween walls 8, 9, and is secured along its side edges to said side walls. The inner walls 4, 5, and wall 6, are similarly outwardly inclined at their upper ends to respectively connect with wall 3 and wall I respectively, at their upper edges the portion 4 and inner wall 6 being secured along their upper edges to the walls 3 and 1 respectively, walls 6, I being integral, if desired, as indicated in Fig. 2. The portion 5 is provided with flange-s along its'side edges, similar to ange II on portion 4, that closely t against the flange or wall II of portion 4 and the wall 8 of the tank respectively, one or bth of the walls II and 8 being provided with projections as at I2 adapted to fit in an upwardly inclined slot or slots I3 provided along the free edges, of the flanges on portion 5, thus removably; securing portion 5 in position with its outer exposed surface ush with the outer exposed surface of portion 4. The portion 5 is easily removed by merely lifting it vertically, and it ls guided into position by coaction between the aforesaid slot or slots I3 and projections I2 when dropped in place.

From the foregoing it is seen that an enclosed vertically Aextending space is provided between the walls 3, 'I and inner walls 4, 6, respectively.

A shortdistance above the bottom I4 of tank I, the portion 4 forming part of the inner wall at one side of the washing tank, and the inner wall 6 opposite thereto, are respectively provided with elongated horizontally extending slots relatively wide, or openings I5, I6, which will be referred to as discharge openings since that is the function they perform, as will be later de-l scribed.

Discharge opening I5 preferably extends from wall 9 to substantially halfway across the tank toward wall 8, while opening I6 preferablyextends from wall 8 to substantially halfway across the tank toward wall 9. These openings are consequently of about equal length, and they are also of substantially the same dimensions and at substantially the same distance from the bottom of the tank.

Supported on the bottom of tank I is a frame generally designated lI1 in the general form of a relatively wide inverted channel strip having depending flanges I8, I9, along opposite sides that rest on the bottom of the tank along their lower edges. This frame is disposed diagonally across the tank I so Athat flange I8 extends "from wall 4 at a Vpoint directly below the inner end of slot I5 to the corner formed by walls 6 and 8, and flange I9 extends from wall 6 at a point directly below the inner end of slot I6 to the corner formed by walls 4 and 9. These flanges are connected at their upper edges by a horizontally extending plate 20 and extending from opposite ends of flange I8, and connected thereto at opposite ends is a horizontally disposed right angle strip 2I extending along walls 8 and 5 and fitting the corner forrned by said walls. This angle strip is hingedly connected by hinges 2I to wall 8, thus allowing the frame Il to be swung upwardly against side 8 for cleaning the bottom of tank I,

The center of the bottom I4 is provided with y an opening in which is tted an inverted funnel-shaped portionv 22 of a casting 22 having a horizontal flange 23 around the lower edge of said funnel-shaped portion, which ange engages the lower side of the bottom around the edge of said opening. This flange is bolted against the bottom by bolts 24. The casting 22 is provided with a central vertical opening extending through the apex of the funnel through which a vertical shaft 25 extends. v This shaft also extends through a stufng box 26 on the underside of the casting around said opening. The-upper end of said slaft 25 is threaded to threadedly engage the hub of a two-bladed screw propeller 2,1, the blades 29 of the propeller being relatively wide and the propeller being wholly disposed below vthe horizontal planeof plate 28, which plate has a large, elongated central opening 23l therein of appreciably greater dimensions than the overall dimensions ofthe propeller. A wire screen 29 is supported on lugs 29" above and free of the propeller, spaced above plate 20 so as to avoid interference with the propeller if the screen sags.

The shaft 25 extends below the aforesaid casting through a bearing 3G provided thereon and at its lower end is provided with a pulley 3l adapted to receive a belt 32 connecting with a pulley 33 of the shaft of an electric motor 34, said motor being secured to a cross-brace 35 extending between supporting legs 36 of the main tank. The motor is inverted with the pulley lowermost so as to keep the motor as close to the tank as is possible and to facilitate changing the pulleys if it is desired to modify the ratio between pulleys.

From the foregoing it is seen that the propeller in the bottom of the dish-washing tank is disposed within a horizontally extending channel formed by the flanges I8, I9, the opposite ends of which channel extend to the Ilower ends of walls 4 and 6 adjacent diagonallyopposite corners of tank I. The lower ends of walls 4 and 6 respectively are cut away at the ends of said channel as at 3l, 38. Extending from the innerend of the opening 31 in the lower end of wall 4, which opening is approximately the same size as opening I5, a rib or strip 40 extends upwardly to the inner end of opening I5 and across the top'thereof to wall 9, thus providing a vertically 'extending conduit'between walls 3 and 4 from opening 3'I to opening I5, and a rib or strip 48' extends from one end 'of the lower opening 38 in wall 6 to the inner end. of opening I6 in said wall and continues around the top of the opening I6 to wall 8, thus providing a similar vertical conduit between opening 38 and opening I6.

The bottom I4 of the washing tank I is generally inclined toward the corner covered by the perforated plate or portion 5, and a drain opening is provided in said corner adapted to removably receive the lower end of an open-ended vertical pipe 43, which pipe extends at its upper end to a short distance below the inclined Alo upper end of the portion 5. This pipe accord- -opening that communicates with an opening 45 in wall 3 at a point spaced above the upper open end of the pipe 43. Thus water in the main tank will pass into the wash tank when displaced by abasket of dishes being placed in the rinse tank and this water is introduced into -the washing tank at a point below the water level in the washing tank. Or Water may be introduced in the rinse tank until it rises to opening 45 to pass into the washing tank.

Screen 29 in the bottom of the washing tank has already been mentioned. 'I'his screen is provided with vertically extending handles 46 at opposite sides, which `handles terminate ,at their upper ends above the water level in the washing tank. The screen 29 may have an upstanding margin forming the frame forthe screen, which frame fits closely Within the area dened by the Walls of the washing tank. Thus the refuse from the dishes that will not pass through the mesh of the screen will be caught by the screen and can easily and quickly be removed by lifting the screen out of the washing tank and jarring or knocking the refuse from the screen. The fact that the propeller draws the water downwardly. through the screen results in holding the refuse by suction against said screen and thus keeps the circulating water free of refuse.

Referring now to the rinse tank, the walls adjacent wall 3 are designated (front) 48, (back) 49, and the end opposite. wall 3 is designated 50. These walls 48 to 58 are double and have heat insulation, such as asbestos, etc., therebetween, as indicated at I.

The bottom 52 of the rinse tank is raised above the level of the bottom I4 of the washing tank, and gas burners 53 are disposed therebelow to heat the water in the tank to the desired tem- .'perature. Steam coils or electrical heating may,

At the bottom of the rinse tank is a screen 55 y removably hinged along one edge to side 46 as at 55 and at the opposite edge the screen is sup-- ported in normally slightly inclined position on a laterally extended end 51 of a vertically disposed rod 58. Rod 58 extends upwardly along a side of the tank and then is doubled on itself, passing through an opening 59 in a shelf 59' at thetop of the tank, and downwardly as at 58' along the outer side of the tank to pivotally connect at its lower end to`one end of a bell crank 5B. Thecrank 86 is pivoted to the side of the tank intermediate its ends and at its end opposite the connection with rod 58' it is pivotally connected to one end of a rod 58', the opposite end of said rod connecting with the end of a handle 5I, said handle being on a water valve 6I for turning and opening the valve upon movement of the screen from its inclined to horizontal position. A coil spring 63 connecting at one end to an end of the bell crank normally maintains the rod 58 in a position so as to yieldably support the screen 55 slightly tilted and also to urg the crank to close the valve 6I" againstl passing water.

Valve 8| is in a water supply pipe 62 and just behind the valve in the same water supply is a needle valve 80 that adjustably regulates the flow gf water from valve 80 for passage through valve Water supply pipe 62 connects with a main supply lpipe 61 at one end and at the opposite end connects with pipe connections 68 which open through a fitting 69 into the upper end of the rinse tank.

In View of the above description, it will be seen that when a basket of dishes is lifted from the washing tank and deposited into the rinse tank, the weight of the dishes on screen 55 will depress the screen to a horizontal position and thus actuate the water valve 6I whereby water is autopass into the washing tank upon rising to opening 45 in the overoW pipe between the two tanks. The water in the rinse tank being heated by the burners, affords a supply of hot water to the washing tank and when the dishes are lifted out of\the rinse tank the flow between the tanks automatically ceases. Of course it is obvious that a treadle or other means may be used to operate the water valve 6 I the idea broadly being to operate the valve by operation of the rinsing oper ation after the dishes are Washed.

It will also be noted that merely by pressing downwardly on the upper end of rod 58, We may manually open valve 6I to fill the washing tank andrinse tank' simultaneously with hot water, the water being heated in the rinse tank. There being no insulation between the washing and rinse tanks, the Washing tank thereafter is kept hot-through b oth the admission of hot water to the washing tank through opening 45 and by circulation of heat through wall 3.

Since screen 55 is only supported on the top of hook 51, the screen may be pivotally lifted to lie alongside wall 48 for cleaning4 the bottom of which cross branch has manually operated valves 1I, 12 at opposite ends thereof disposed in front of the washing and rinse tanks as indicated in Fig. 1. From valve 1I the heretofore mentioned pipe 68 leads to the fitting 69, so that a manual injection of water into the rinse tank may be had as desired without operating screen 55.

From valve 12 a pipe 13 leads to a portion of fitting 69 that has a separate outlet 13 adapted to discharge'water into the dish-washing tank, thereby providing manual control for injecting water into the dish-washing tank as desired.

The basket used for dishes is-a wire basket substantially the same in shape and size as the screen 29' except that the mesh is much larger to permit refuse to pass therethrough and onto the screen 29' and it is provided with high screen sides for retaining the dishes in position therein. The dish basket has handles similar to thelhandlesof screen 29' for lifting the basket from one tank to the other, this basket not being shown since it is deemed unnecessary.

When the dishes are in the basket and in the dish-washing tank, the discharge slots I5, i6, are adapted to eject the water upwardly toward and between the dishes, such as large plates set edgewise or transversely of the plane of the slots I5, I6. Thus no portion of the dishes is out of the maximum force of the Water and a complete scouring takes place.

The walls 6 and 4 may, of course, be termii nated immediately Iabove openings I5, I6, if desired, and the connection between openings I5, 31 and I6, 38, respectively, may be separately formed U-shaped conduits, but the structure shown is economical to make and provides a washing tank with straight sides, the tapered upper ends of walls 4 and 6 greatly assisting in quickly guiding the dish basket into place.

One point in particular is to be considered in this invention. High pressure injection nozzles for spraying the dishes are of no value in this invention. We have found that one of the most essential things is to provide for circulating the body of water in the washing tank bodily as rapidly as is possible, and by disposing the openings I5, I6, as shown relative to the propeller and channels leading therefrom, the body o-f water is moved into and out of the tank and through the dishes many times without splashing and yet the dishes are scoured cleanin a minimum of time.

Having described our invention, we claim:

1. Apparatus for washing dishes comprising av` tank for water having a bottom and sides, a horizontal screen positioned adjacent the bottom of the tank spaced thereabove for supporting dishes thereon, a power driven propeller positioned between the screen and bottom arranged and adapted for drawing water in the tank downwardly through the screen upon actuation thereof, a generally vertically extending relatively short conduit at one side of Vthe tank terminating at its lower and upper ends respectively in laterally directed inlet and outlet openings communicating with the interior of the tank, said inlet opening being positioned -adjacent the bottom of the tank below the level of the screen and the. outlet opening being positioned above the level of the screen and closely adjacent thereto, a pair of spaced opposed walls,4 other than the lateralsides of the tank, extending from opposite lateral side edges of said inlet opening, said pair of opposed walls being disposed over the bottom of the tank, and below said screen and past: the propeller at opposite sides thereof fordirecting water drawn downwardly by the propeller toward said inlet opening.

2. Apparatus for washing dishes comprising al tank for water having a bottom and including two opposed flat side walls, a horizontal dish supporting screen positioned adjacent the bottom of the tank and spaced thereabove, a horizontally disposed powerl driven propeller disposed between the screen and bottom arranged and adapted for drawing water in the tank downwardly through the screen upon actuation thereof, a relatively short generally vertically extending conduit disposed adjacent each of the opposed at side walls of the tank, each of the conduits terminating at its lower end in .a laterally directed inlet communicating with the space between the bottom and screen and opening toward the propeller and said conduits terminating at their upper ends in outlets communicating with the inside of the tank adjacent the upper side of the screen whereby 4water drawn downwardly by the propeller will be deflected by the bottom toward the inlet openings for passing into the conduits `and out of the outlet openings, said outlets being arranged to direct water ejected therethrough in a lateral and upward direction toward the at side of the tank opposite thereto, and said outlets being horizontally offset relatively and the flat side of the tank directly opposite each outlet being imperforate whereby water ejected from each of the outlets respectively will be deected by the imperforate flat-side directly opposite thereto.

3. In a construction .as defined in claim 2, said outlets being positioned wholly below a horizontal plane disposed midway between the Vupper and lower ends of the tankand means for maintaining the normal Water level in the tank at an elevation above such plane.

4. Apparatus for `washing dishes comprising a tank forwater having a bottom and including two opposed at side walls, a horizontal dish supporting screen positioned adjacent the bottom of the tank and spaced thereabove, a power driven propeller disposed between the screen and bottom arranged and adapted for drawing water in the tank downwardly through the screen upon actuation thereof, a relatively short 'generally vertically extending conduit disposed adjacent each of the opposed flat side walls of the tank,

- each of the conduits terminating at its lower end in a laterally directed inlet communicating with the space between the bottom and screen and.

terminating at its upper end in an outlet communicatin-g with the inside of the tank adjacent the upper side' of the screen, said outlets being arranged to direct water ejected -therethrough in a lateral and upward direction towards the 'dat side of the tank opposite thereto, and said outlets being horizontally oiset relatively and the flat side of the tank directly Opposite each outlet being imperforate whereby water ejected 'from each of the outlets respectively will be deflected by the imperforate iiat side directly opposite thereto, a pair of spaced opposed walls extending across the bottom of the tank past opposite sides of the propeller to opposite side edges of the inlets for guiding water drawn downwardly by the propeller to said inlets, said propeller being positioned substantially midway between said opposed dat sides.

5. Apparatus for washingtdishes comprising a tank for waterI having a bottom and including two opposed flat side walls, a horizontal dish supporting screen positioned adjacent the bottom of the tank and spaced thereabove, a power driven propeller disposed between the screen and bottom arranged and adapted for drawing water in the tank downwardly through the screen upon actuation thereof, a relatively short generally vertically extending conduit disposed adjacent each of the opposed flat side walls of the tank, each of the conduits terminating at its lower end in a laterally directed inlet communicating with the space between the bottom and screen and terminating at its upper end in an outlet communicating with the inside of the tank adjacent the upper side of the screen, said outlets being arranged to direct water ejected therethrough in a lateral and upward direction toward the flat side of the tank opposite thereto, and said out- 'lets being horizontally oiset relatively and the flat side of the tank directly opposite each outlet being imperforate whereby water ejected from each of the outlets respectively will be, deflected by the importante ilat 'side directly opposite thereto. guide means on the bottom of the tank arranged for directing water drawn downwardly by the pxopellel' toward said inlets for passage through the conduits and election back into the Y tnnkvthrouth outlets, and the sides oi the tank other than'sald two opposed llat side walls being imperiorate whereby the water drawn downwardly by the propeller will be ejected back into the tank through the two outlets only.

' WILLIAM R. ADAMS. GORDON B. GRACE. 

